1. Field of the Invention
The present invention concerns an apparatus for wet grinding of welding electrodes, such as tungsten electrodes.
2. Description of the Prior Art
For use in TIG welding (tungsten inert gas welding) and plasma welding, tungsten welding electrodes are used to achieve weld seams of high quality which have a well-defined pointed end. Surface properties as well as dimensions of the electrode point have particular significance in generating the required electric arc produced by the electrodes which melts the welding wire for producing the weld seam.
At the same time, the welding electrode is subjected to heavy wear due to the temperatures occurring at the site of welding operation. After a short period of time, the welding electrode is not capable of producing weld seams of high quality. In practice, the welder carries welding electrodes in order to replace them in the welding equipment. Alternatively, the welding electrodes are to ground again which, however, requires that the workplace has a mobile electrode grinding apparatus.
Grinding apparatuses of this type normally operate with a rotating grinding wheel which grinds the welding electrodes to a point by pressing the electrodes against a side face of the grinding wheel at a desired angle. This grinding principle makes it complicated to vary the grinding angle or the point of the electrodes.
It is known that this grinding principle and apparatus have unsolved work environmental problems in connection with the aggressive grinding which produces dust formed by grinding welding electrodes containing tungsten.
DK/EP 0822882 T3 discloses an apparatus for grinding welding electrodes, in particular tungsten electrodes. The apparatus includes a drive motor for a rotating grinding wheel and apparatus adapted to fix a welding electrode at a certain angle relative to the grinding wheel, wherein the fixing apparatus includes a part which is held in a vertically extending guide and is displaceable in parallel with the plane of the grinding wheel. This apparatus has two mutually displaced insertion openings or positions for an electrode holder which are a first insertion opening or position opposite an arched angle scale corresponding to the radius of the grinding wheel, and a second insertion opening or position situated for fastening the electrode in parallel with the plane of the grinding wheel with the vertical spacing between the insertion openings being equal to the spacing between the arched angle scale and the grinding wheel.